In the past few years, there has been increased interest by the water treatment industry in the use of ferrate salts as, e.g., a possible substitute for chlorination processes. For example, potassium ferrate may be used in the treatment and purification of water (see Murmann et al, "Experiments Utilizing FeO.sub.4 -2 for Purifying Water", Water Research, Vol. 8, pp. 79-93 (1974); Gilbert et al., "An Investigation of the Applicability of Ferrate Ion for Disinfection", J. Am. Water Works, Vol. 68(9), pp. 495-497 (1986); and Waite et al., "Iron (VI) Ferrate as a General Oxidant for Water and Wastewater Treatment", Ozone/Chlorine Dioxide Oxid. Prod., Org. Matter Process Conference, (1976), published 1978, pp. 410-425). Ferrate salts are also known as useful for precipitation and/or coagulation of solids in the wastewater.